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An Ohio inmate is arguing that the death penalty would be cruel and unusual punishment for him because he is obese.

Ronald Post is sentenced to receive the death penalty on January 16, 2013 for the murder of Helen Vantz, a hotel clerk, thirty years ago. But at 480 pounds, he says that his weight, medical history, scar tissue and access to his veins will cause his executioners serious problems.

Condemned Ohio inmates face a single dose of pentobarbital, usually injected into the arm. But medical professionals have had difficulty inserting needles into Post's arms before. Four years ago, an Ohio State University medical nurse needed three tries before she was able to successfully insert an IV drip into his arm.

He also says that his weight means that he may not be able to fit on the execution gurney. And, because of knee and back problems, he has had difficulty exercising to lose the weight. The filing said that he had attempted to use the exercise bike in prison, but that it collapsed under his weight.

This is not the first time that prisoners' weight has been an issue. In 2008, lawyers attempted to argue that convicted double-killer Richard Cooey was too obese for lethal injection, due to prison food and limited opportunities to exercise. Cooey was 5-foot-7 and weighed 267 pounds. Coeey was executed in October of 2008.

In 2007, it took Ohio prison officials two hours to insert IVs into the veins of Christopher Newton. Newton weighed 265 pounds.

In 1994, in Washington state, a judge upheld Mitchell Rupe's conviction but said that, at 400 pounds, hanging would be impossible due to the risk of decapitation. Rupe died in prison in 2006.

A spokeswoman for the prisons department had no comment on Post's case.